Asphalt compaction device

ABSTRACT

In one embodiment of the invention, a traditional roller, known in the industry, includes a front drum including an eccentric which provides a vibration which is transmitted to the surface to be compacted and a rear drum including another eccentric which provides another vibration which is also transmitted to the surface to be compacted. While this traditional roller is well known in the art, it may be modified to including a control box which synchronizes the movement of the eccentric of the front roller and the eccentric of the rear roller and a braking mechanism. While the braking mechanism is engaged, the synchronized vibrations of the front and rear roller allow the roller to continue compacting the warm asphalt without producing a pressure wave in front of the roller. The synchronization may also be controlled by the control box so that the vibrations created by the eccentrics may actually propel the roller forward.

This patent application is a continuation-in-part of a previouslysubmitted patent application, namely, patent application Ser. No.11/133,694, entitled ASPHALT COMPACTION DEVICE, which was filed on May20, 2005 and the inventor of which is William D. McCoskey.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is related in general to the field of construction. Inparticular, the invention consists of a device and method for improvedcompaction of asphalt.

2. Description of the Prior Art

Asphalt is a material well-known in the construction industry used tocreate a surface for supporting vehicles. In this capacity, asphalt isoften used to create both parking lots and roads. However, theapplication of asphalt requires many disparate steps to ensure that thefinished surface is both smooth and durable.

In order to properly apply asphalt, it is necessary that the asphalt bedeposited on the intended surface after it has been heated to a hightemperature, producing a pliable and workable material. The requiredtemperature for application may vary based on ambient environmentalconditions, the intended use of the product, and local regulations.Those skilled in the art of applying asphalt can readily ascertain theappropriate application temperature.

Once asphalt has been applied, it must be compacted to increase itscohesiveness, to prevent water seepage, and to resist cracking andsplitting due to use and changes in its ambient environment. Manymethods of compacting asphalt are well known in the art. For example,one method entails the use of large heavy rollers to exert force on theasphalt. However, these rollers not only produce force normal to thesurface, but also tend to push the asphalt in front of the roller,forming a ridge or wave of semi-fluid material. In order to reduce thiseffect, some applications involve rolling newly applied asphalt once ortwice and then waiting an extended period of time before rolling thematerial again. This waiting period extends the time needed to finishthe application of the asphalt. Accordingly, it is desirable to have ameans for compacting asphalt that reduces or eliminates the wait periodinherent in the use of large rollers.

Another method of asphalt compaction entails utilizing a vibratingplate. This plate is often first pushed over the seams of the newlyapplied asphalt to seal the material where it meets asphalt that hasbeen previously applied. This is especially useful when the asphaltapplication is for a patch or repair of previously applied asphalt. Oncethe edges of the new application has been sealed, the vibrating plate isthen passed over the rest of the new application, applying a normalforce that increases the cohesiveness and seals the asphalt. Using avibrating plate eliminates the formation of the pressure ridgeencountered when using heavy rollers. Accordingly, waiting periods maynot be required between passes using a vibrating plate. However,traditional vibrating plates do not produce compaction levels equivalentto those produced by heavy rollers. This results in most asphaltapplications either exclusively using heavy rollers with theircorresponding wait periods or first using a vibrating plate followed bythe use of a heavy roller. Accordingly, it is desirable to have a devicethat can produce compaction levels equivalent to those produced by heavyrollers without the associated wait periods and without requiringmultiple pieces of equipment.

SUMMARY OF THE INVENTION

The invention disclosed herein utilizes a vibrating plate with one ormore secondary surfaces used to concentrate and localize the forceapplied by the vibrating plate. The newly improved vibrating plate maybe either a small push-type model that can be moved and steered by auser or a large, articulated machine. The secondary surfaces may eitherextend across the width of the primary vibrating plate or may include adynamic shape and size to increase the compaction effectiveness.

In one embodiment of the invention, a traditional roller, known in theindustry, includes a front drum including an eccentric which provides avibration which is transmitted to the surface to be compacted and a reardrum including another eccentric which provides another vibration whichis also transmitted to the surface to be compacted. While thistraditional roller is well known in the art, it may be modified toincluding a control box which synchronizes the movement of the eccentricof the front roller and the eccentric of the rear roller and a brakingmechanism. While the braking mechanism is engaged, the synchronizedvibrations of the front and rear roller allow the roller to continuecompacting the warm asphalt without producing a pressure wave in frontof the roller. The synchronization may also be controlled by the controlbox so that the vibrations created by the eccentrics may actually propelthe roller forward.

In a modification of this last embodiment, the rear roller may bereplaced with a set of pneumatic wheels. While the braking mechanism isengaged on the front roller, allowing the eccentric to produce avibration for compacting the warm asphalt, the rear pneumatic tirespropel and guide the roller.

Various other purposes and advantages of the invention will become clearfrom its description in the specification that follows and from thenovel features particularly pointed out in the appended claims.Therefore, to the accomplishment of the objectives described above, thisinvention comprises the features hereinafter illustrated in thedrawings, fully described in the detailed description of the preferredembodiments and particularly pointed out in the claims. However, suchdrawings and description disclose just a few of the various ways inwhich the invention may be practiced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a vibrating compaction device with aprimary plate and a secondary compaction plate, according to theinvention.

FIG. 2 is an illustration of a vibrating compaction device with asecondary compaction plate that can be extended and retracted.

FIG. 3 is an illustration of an articulated vibrating compaction devicewith a pair of primary compaction plates and a secondary compactionplate, according to the invention.

FIG. 4 is an illustration of the articulated vibrating compaction deviceof FIG. 4 illustrating the application of the secondary compactionplate.

FIG. 5 is an illustration of an articulated vibrating compaction devicewith a secondary compaction plate that can be extended and retracted.

FIG. 6 is an illustration of an asphalt compaction device, according tothe invention, including a modified traditional roller with asynchronization unit and a braking mechanism.

FIG. 7 is an illustration of the asphalt compaction device of FIG. 6wherein the rear roller drum has been replaced with a set of pneumaticwheels.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

This invention is based on the idea of using multiple compaction platesof varying shapes and sizes to concentrate the force applied by avibrating compaction plate to increase compaction rates of newly appliedasphalt. Referring to figures, wherein like parts are designated withthe same reference numerals and symbols, FIG. 1 is an illustration of avibrating compaction device 10 with a primary compaction plate 12 and asecondary compaction plate 14, according to the invention. The primarycompaction plate 12 is similar to those well-known in the art of asphaltcompaction devices. A motor 16 or engine provides an up-and-downmovement of the primary compaction plate 12 resulting in a vibration ofthe plate against the surface of the asphalt. A user pushes and steersthe vibrating compaction device 10, which is facilitated by thereduction of force exerted by the vibrating compaction device 10 duringeach cycle of its vibration.

The vibrating compaction device 10 may be rotated to bring the secondarycompaction plate 14 in contact with the surface of the asphalt. In thisembodiment of the invention, the secondary compaction plate is the samewidth as the primary compaction plate 12 but has a smaller lengthresulting in a small footprint. The motor 16 continues to produce aforce equivalent to that normally applied through the primary compactionplate. However, since the footprint of the secondary compaction platehas a smaller contact area, the force exerted by the vibratingcompaction device 10 is concentrated into a smaller area. In thismanner, the ability of the vibrating compaction device 10 to compact theasphalt is increased, resulting in a higher compaction rate than can beachieved using the primary compaction plate 12.

Alternatively, the primary compaction plate 12 may be integrated withthe secondary compaction plate 14 to form a unified compaction platewith a first and second surface. Here, the second surface is affixed tothe first surface in a manner that forms a 135 degree angle between thetwo surfaces. However, the invention is not limited to any specificangle and may include an angle equal to or greater than 90 degrees andless than or equal to 180 degrees.

The vibrating compaction device 10 may also include a tertiarycompaction plate 20. In this embodiment of the invention, the tertiarycompaction plate 20 has a width which is less than that of the primarycompaction plate 12. Additionally, the tertiary plate may be formed inthe shape of a semi-circle, an ellipse, a free-form shape, a triangle,or other polygon. Because the surface area of the tertiary compactionplate 20 is less than that of the primary compaction plate 10 and thesecondary compaction plate, the tertiary compaction plate 20 may be usedto apply even more force to the surface of the asphalt, thus increasingthe rate of compaction. The non-traditional shape of the tertiarycompaction plate 20 may be used to concentrate the force of thevibrating compaction device 10 along a focused path, such as a seam ornewly filled-in trench. In an alternate embodiment of the invention, thesecondary compaction plate may also include a non-traditional shape suchas a semi-circle, ellipse, free-form shape, triangle, or other polygon.Additionally, the primary compaction plate 10 may include a plurality ofsurfaces including a primary, secondary, and tertiary surface. The angleformed by the tertiary surface and the primary surface may be greaterthan or equal to 90 degrees and less than or equal to 180 degrees.

FIG. 2 is an illustration of a vibrating compaction device 10 with asecondary compaction plate 14 that can be extended and retracted withrespect to the primary compaction plate 12. In this embodiment of theinvention, the width of the secondary compaction plate 14 is the same asthat of the primary compaction plate 12. However, the secondarycompaction plate 14 may assume any width, either less than, equal to, orgreater than that of the primary compaction plate. Likewise, while thisembodiment of the invention includes a rectangular secondary compactionplate 14, the secondary compaction plate 14 may assume any shape. Theresult is that the secondary compaction plate 14 may be extended awayfrom the primary compaction plate resulting in a focused application ofthe vibrating compaction device's downward force. Additionally, thesecondary compaction plate 14 may be retracted so that its applicationsurface (side facing the asphalt) is flush with or recessed above thatof the primary compaction plate.

FIG. 3 is an illustration of an articulated vibrating compaction device100 with a pair of primary compaction plates 112 and a secondarycompaction plate 114, according to the invention. In this embodiment ofthe invention, the articulated segments 116 are used to steer thearticulate vibrating compaction device. A first primary compaction plate112 a may be rotated that the secondary compaction plate 114 is appliedto the surface to be compacted, as illustrated in FIG. 5. Additionally,the articulated vibrating compaction device 100 may include additionalsecondary compaction plates or tertiary compaction plates 118.

FIG. 5 is an illustration of an articulated vibrating compaction device100 with a secondary compaction plate 114 that can be extended andretracted with respect to one of the primary compaction plates 112.While this embodiment of the invention includes a rectangular secondarycompaction plate 114, the secondary compaction plate 114 may assume anyusable shape. The result is that the secondary compaction plate 114 maybe extended away from the primary compaction plate resulting in afocused application of the vibrating compaction device's downward force.Additionally, the secondary compaction plate 114 may be retracted sothat its application surface (side facing the asphalt) is flush with orrecessed above that of the primary compaction plate.

FIG. 6 illustrates yet another embodiment of the invention, namely, anasphalt compaction device 200 including a traditional roller compactor,known in the industry, including a front roller 202 having a firsteccentric 206 which produces a vibration which is transmitted to thesurface to be compacted and a rear roller 204 having a second eccentric208 which provides another vibration which is also transmitted to thesurface to be compacted. While a traditional roller is well known in theart, in this embodiment of the invention, the asphalt compaction device200 includes a synchronization unit 210 which synchronizes the movementof the first eccentric 206 of the front roller 202 and the secondeccentric 208 of the rear roller 204 and a braking mechanism 212. Whilethe braking mechanism 212 is engaged, the synchronized vibrations of thefront roller 202 and rear roller 204 allow the asphalt compaction device200 to continue compacting the warm asphalt without producing a pressurewave in front of the device. This synchronization may also be controlledby the synchronization unit 210 so that the vibrations created by thefirst eccentric 206 and second eccentric 208 may actually propel theasphalt compaction device 200 forward.

In yet another embodiment of the invention, as illustrated in FIG. 7,the asphalt compaction device 200 may include a set of pneumatic wheels214 instead of the rear roller 204. While the braking mechanism isengaged on the front roller, allowing the first eccentric 206 to producea vibration for compacting the warm asphalt, the set of pneumatic tires214 propel and guide the asphalt compaction device 200.

Those skilled in the art of making asphalt compaction systems maydevelop other embodiments of the present invention. However, the termsand expressions which have been employed in the foregoing specificationare used therein as terms of description and not of limitation, andthere is no intention in the use of such terms and expressions ofexcluding equivalents of the features shown and described or portionsthereof, it being recognized that the scope of the invention is definedand limited only by the claims which follow.

1. A vibrating compaction device, comprising: a roller compactorincluding a front roller having a first eccentric and a rear rollerhaving a second eccentric; a braking mechanism adapted to lock the frontroller; and a synchronization unit adapted to synchronize a firstvibration produced by the first eccentric and a second vibrationproduced by the second eccentric.
 2. The vibrating compaction device ofclaim 1, wherein the braking mechanism is further adapted to lock therear roller.
 3. The vibrating compaction device of claim 1, wherein thesynchronization unit is adapted to cause the first vibration and thesecond vibration to propel the vibrating compaction device in a forwarddirection.
 4. A vibrating compaction device, comprising: a rollercompactor including a front roller having an eccentric; at least onepneumatic wheel; and a braking mechanism adapted to lock the frontroller, wherein the eccentric produces a vibration.
 5. The vibratingcompaction device of claim 4, wherein the at least one pneumatic wheelpropels the vibrating compaction device in a forward direction.
 6. Thevibrating compaction device of claim 4, wherein the at least onepneumatic wheel guides the vibrating compaction device.
 7. A vibratingcompaction device, comprising: a roller compactor including a frontroller having an eccentric; and a braking mechanism adapted to lock thefront roller, wherein the eccentric produces a vibration when said frontroller is locked.